We've found that simple ethanol precipitation after drying down produces
much cleaner oligos. We just centrifuge the oligo after resuspending, and
add 1/10 vol NaOAc and 2 volumes of EtOH to the supe.
>>>We have just made some oligos for PCR on a 50pmol scale, cleaved them from
>>the column, deprotected and dried them down. When they are redissolved in
>>water there is visible rubbish in the tube, which does spin down. I have
>>tried using the clear supernatant, diluted, in a PCR reaction and get
>>nothing. My question is, does anyone know if dirty primers can inhibit the
>>PCR reaction? And if so what is the best method (and simplest) for
>>cleaning them up?>Jo Caine
>>We received some commercially prepared primers in a similar state, which did
>not work properly. The issue was not resolved entirely, but seemed to be
>due to material coming off the column. The material from the column
>resulted in a spuriously high OD value, resulting in over dilution of the
>primers (i.e. it was difficult to know how much primer we had), rather than
>the dirty primers interfering with PCR.
>>